Method for treatment and disinfection of industrial effluents

ABSTRACT

The invention relates to the methods for sewage treatment contaminated by mechanical impurities, fats, proteins and other organic and inorganic compounds, and can be used for purification and water disinfection contaminated by heavy and radioactive metals, saturated or unsaturated fats, filtrate from landfills for solid household waste, disposals of meat processing plants, and water contaminated with oil and petroleum products. The method for treatment and disinfection of industrial wastewater includes flotation, electrocoagulation and filtration. The new is that the method also provides: mixing water with powder hydrophobic carbon-based sorbent with high absorbing capacity; filtration of a suspension of water and a carbon sorbent on a rubber-based hydrophobic sorbent; decomposition of saturated and unsaturated fat, oil, petroleum products and other organic substances accumulated on carbon and rubber sorbents; floatation in flow mode with the addition of hydrogen peroxide; recovery of the active substance in the presence of hydrogen peroxide; and its further reuse; electrocoagulation in flow mode with water saturation with oxygen and hydrogen, formed on indispensable carbon or metal electrodes, and on the active substance based on the of aluminum, titanium, sodium, tin, copper, and other metals; water disinfection by electro-cavitation; generation of active substance based on the iron and titanium atoms; water filtration on the precoat filter, filtering on activated carbon filter.

The invention relates to the area of treatment for effluentscontaminated with mechanical inclusions, fats, proteins and otherorganic and inorganic compounds and can be used for the treatment andwater disinfection contaminated with heavy and radioactive metals,saturated or unsaturated fats, filtrate from landfills for solidhousehold waste, disposals of meat processing plants and watercontaminated with oil and petroleum products.

The “Method of electrochemical water decontamination” is known toinclude its treatment in the anode and cathode chamber of the diaphragmelectrolyzer, with the anode camera operating in flow mode, and thecathode camera operating in non-flow mode. (Patent of Ukraine No.111278)

The disadvantage of the method is that the method involves onlyelectrochemical water disinfection, due to this, has a narrow range ofapplications.

The closest to the claimed invention is: “The method of electrochemicalmeat plants sewage purification”, which includes electrocoagulation inan electrolyzer with soluble electrodes, coagulation with denaturationof proteins, and flotation. In this case, before electrocoagulation, theprotein-fatty waste is purified from mechanical inclusions and notemulsified fats and mixed with drained manure, pre-purified frommechanical inclusions. After this, the average runoff from pH 5.6-6.0 isprocessed in an electrocoagulator with iron electrodes at oxygensaturation up to 2-4 mg/l, then with hydrogen peroxide, lime,flocculant, and the sludge is removed by settling and filtration, withfiltrate treated with an electric flotator at a pH of 9-10,simultaneously feeding hydrogen peroxide. After the sludge removal, thewaste is treated with sodium hypochlorite and is sequentially filteredthrough a carbon-loaded filter, cation-exchange and anion exchangefilters. (Patent of the Russian Federation No. 2396217).

The disadvantage of the known method is that the technical solution canbe used only for the treatment of sewage from meat plants and does notallow to reduce the concentration of heavy and radioactive metal ions inwater, and leads to waste formation that needs to be disposed at thelandfill. The method does not include water disinfecting.

The purpose of the invention is to improve the method of treatment anddisinfection for industrial effluents and to expand the scope of itsapplication, namely: to reduce the concentration of organic substances,heavy and radioactive metal ions in water, to increase the efficiency ofremoval fats of vegetable or animal origin, of oil or petroleum productsfrom the contaminated water and to achieve disinfection for the purifiedwater.

The technical result of the claimed invention is that the application ofnew materials, in combination with the known purification techniques forcontaminated water, can reduce the concentration of organic substances,heavy and radioactive metal ions in water, achieve the complete removalof fats of vegetable or animal origin, oil or petroleum products fromcontaminated water, and to achieve decontamination of purified water.

The task is solved by using a purification and disinfection method forindustrial effluents, which, in addition to the flotation,electrocoagulation and filtration stage, includes the following steps:

-   -   mixing water with carbon-based powder hydrophobic sorbent of        high absorbing capacity for saturated, unsaturated fats, oil and        petroleum products and accumulation of pollutants on a        hydrophobic sorbent;    -   filtration of a water suspension and a carbon sorbent on a        rubber-based hydrophobic sorbent;    -   decomposition of saturated and unsaturated fats, oil, petroleum        products and other organic substances accumulated on carbon and        rubber sorbents, in the form of foam and solid organic        particles, by pyrolysis without oxygen to carbon monoxide;    -   floatation in the flow mode adding hydrogen peroxide and        saturating water with oxygen formed during the decomposition of        water and hydrogen peroxide molecules on the active substance        particles based on the aluminum, titanium, sodium, and other        metals atoms, which is a catalyst for the process of molecules        decomposition with the OH- and O-ions formation, simultaneously        absorbs organic molecules and ions of heavy metals removing        foam, followed by its utilization during the spent sorbents        regeneration;    -   regeneration of the active substance with hydrogen peroxide and        directing it for reuse;    -   flow mode electrocoagulation with water saturation by oxygen and        hydrogen, which is formed on indispensable carbon or metal        electrodes and on an active substance based on the aluminum,        titanium, sodium, and other metals atoms, which adsorbs organic        compounds on its surface and generates OH-, O-ions under normal        pressure with foam removal;    -   water decontamination by electrocavitation, which is formed by        high-voltage discharges in the medium of iron and copper        particles or iron- and copper-based alloys, with titanium diode        electrodes, and the generation of the active substance based on        the iron and titanium atoms for further organic matter        oxidation, decomposition in the flow of organic matter        preferably by OH- and O-ions with hydrogen peroxide and active        substance based on the iron, titanium, copper, sodium, and other        metals with calcium oxide (CaO) and then activated charcoal        filter at high pressure;    -   water filtration on a precoat filter under pressure to remove        more than 5 microns solid and colloidal particles from water,        using kieselguhr as a substrate and an active substance based on        aluminum, titanium, copper, and sodium as an precoat membrane;    -   electrodialysis under pressure to reduce the ions level in        water;    -   water filtration on activated charcoal filter.

The decomposition of pollutants on carbon and rubber sorbents bypyrolysis is carried out using microwave energy and the conversion oforganic compounds to the synthesis gas (CO, H₂), followed by the use ofsynthesis gas for the thermal and electric energy generation. The ratioof the particle surface for the active substance based on the aluminum,titanium, sodium, iron atoms, which are the catalyst for thedecomposition of molecules with the formation of OH- and O-ions, to theweight of their particles is more than 50, with a large volume of microand mesopores. Adding from 1 to 20 ml/l of hydrogen peroxide to water,the ratio for the active substance is in the range from (1:0.5) to(1:5).

Electrolysis of water in flotation reactors with an active substancebased on the aluminum, titanium, sodium, iron and hydrogen peroxideatoms is carried out on metal electrodes (stainless steel, copper,aluminum) or carbon material, with a direct current of 3 to 240 V andthe current density on the electrodes within the range from 0.01 A/cm²to 2 A/m².

Water disinfection is carried out in an electrochemical reactor of aspecially designed structure with ultraviolet radiation, ultrasonicwaves, cavitation waves, which are formed in the reactor by directcurrent pulses in the range from 300 to 3000 V on titanium electrodesloaded into the intercolectric space of metal particles (iron, aluminum,copper separately or in combination in different proportions) in thesize from 3 mm to 10 mm, which generates the formation of activesubstance from 0.1 mg/l to 30 mg/l based on the iron, copper, aluminum,titanium oxides with or without the addition of NaCl into the reactor inconcentration of 0.5 g/l to 30 g/l, adding or not adding hydrogenperoxide in concentration of 0.5 ml/l to 10 ml/l. Oxidation of organicmatter residues is carried out in a high-pressure reactor, withpressures ranging from 3 to 10 atm.

Significant features of the invention are the following:

-   -   the use of carbon-based powder hydrophobic sorbent with a high        absorption coefficient for saturated and unsaturated fats, oils        and petroleum products from water, with its own formula for the        removal of the above-mentioned substances from water;    -   the use of a hydrophobic rubber-based sorbent to separate the        suspension into water and powder sorbent with accumulated        saturated and unsaturated fats, oil and petroleum products,        removal of solid particles with the size of more than 0.1-1 mm,        removal of other solvents interacting with rubber;    -   conversion of saturated and unsaturated fats, oil and petroleum        products, solvents and solid organic particles removed from        water into synthesis gas used to generate thermal and electric        energy for technological needs in a reactor of its own design        using microwave energy;    -   the removal of other organic compounds in colloidal form and of        heavy and radioactive metals ions at the flotation stage in the        presence of the active substance of its own formula and hydrogen        peroxide in the flotator of its own design, in a flow mode;    -   the oxidation of organic matter remaining in water with OH- and        O-ions, preferably under pressure in the presence of an active        substance of its own formula and hydrogen peroxide, with the        increased pressure generated by oxygen, which is obtained from        water and hydrogen peroxide molecules in the presence of the        active substance in reactor of its own design, with periodic        electrolysis of water on non-inverting carbon electrodes;    -   the oxidation of organic matter with OH- and O-ions, preferably        under pressure, in the presence of activated carbon, calcium        oxide and hydrogen peroxide, with the increased pressure        generated by oxygen, which is generated from water and hydrogen        peroxide molecules in the presence of the active substance in        the reactor of its own design;    -   the water disinfection by OH- and O-ions, ultraviolet radiation,        ultrasonic radiation, cavitation waves, which are generated in        the electrocavitation process, created by the high-voltage        pulses generator in the reactor of its own design;    -   the removal of solid particles with the size of more than 5        microns, heavy and radioactive metals oxides, on a precoat        filter under pressure using kieselguhr and an active substance        of its own formula as an precoat membrane;    -   the reduction of the ions level in water by electrodialysis;    -   the installation of equipment in standard size containers.

The technical result of the claimed invention is that the application ofnew materials in combination with known techniques for purification ofcontaminated water can reduce the concentration of organic substances,heavy and radioactive metal ions in water and remove fats of vegetableor animal origin, petroleum or petroleum products from contaminatedwater. The essential features of the present invention allow thepurification for the water contaminated with organic compounds, heavyand/or radioactive metals and their decontamination with minimalapplication of electrical energy by using the active substance andhydrogen peroxide to generate OH- and O-ions, which are the mainoxidants, to form a high pressure in the system by the emitted gases,and for the generation of thermal and electric energy, using thesynthesis gas formed during the decomposition of organic pollutants as afuel and regeneration of spent carbon sorbents.

Another technical result is that the efficiency of treatment for highlycontaminated water is achieved by the application of the activesubstance and hydrogen peroxide to generate OH- and O-ions, mainly dueto the use of gases generated for increasing the pressure, reducing thetime of water purification due to the oxidation of organic compoundsunder elevated pressure, reuse of sorbents and activated carbon aftertheir regeneration, placing equipment in standard sizes containers,which significantly reduces the cost for preparing premises andequipment installation.

The method is implemented as follows. The removal of fats of plantand/or animal origin, oil and/or petroleum products, saturated andunsaturated fats from contaminated water, which is a stable water-fatemulsion, is carried out by forming a suspension of water and acarbon-based powder hydrophobic sorbent in the rate of 1 to 10 g per oneliter of water, the subsequent mixing of the suspension with ahydrophobic rubber-based sorbent, filtration of a water suspension andsorbents on a rubber-based sorbent on one or more specially designedfilters and the supply of water free from saturated and unsaturatedfats, including oil and petroleum products (the degree of purificationfrom fats and petroleum products reaches 99.9%) into the flotationreactor. Regeneration of spent sorbents with accumulated fats andpetroleum products in one or more sorbent regeneration reactors and theconversion of exhaust gases with microwave sources, conversion of theexhaust gases into the synthesis gas, which is a fuel for obtainingelectric and thermal energy at the cogeneration plant, reusing ofregenerated sorbents for the removal process of saturated andunsaturated fats, including oil and petroleum products from contaminatedwaters. Removal in two or more flotation reactors with foam up to 80% oforganic substances from water, which is achieved by adding to water theactive substance of a special formula based on the of aluminum,titanium, sodium, iron atoms with a ratio of surface area to particleweight more than 50. The size of the micro- and mesopores, for theconcentration from 0.1 to 20 g/l in the reactor, and the addition from0.5 to 10 ml/l of hydrogen peroxide to water (60% of the total volumerequired for full oxidation of the organic component) in relation to theactive substance in the range from (1:0.5) to (1:5) in combination withelectroflotation under atmospheric pressure in a reactor of a specialdesign, while the active substance remains in the reactor until it issaturated with heavy and/or radioactive metals, while water changesconstantly. The oxidation of organic matter in the flotation reactors,which remains in the dissolved state in water, predominantly by OH- andO-ions, which are formed from the decomposition of water and hydrogenperoxide molecules on the surface of an active substance absorbingorganic molecules and generating OH- and O-ions on its surface thatreact with nearby organic molecules, the reaction proceeds with theformation of free radicals of organic molecules, which are active andenter the recombination reaction between themselves and deeper oxidationin the reaction with the OH- and O-ions. The oxidation of heavy andradioactive metal ions in flotation reactors mainly by OH- and O-ions,which are formed from the decomposition of water and hydrogen peroxidemolecules on the surface of an active substance absorbing heavy andradioactive metal ions and generates on its surface OH- and O-ions,which react with adjacent ions, and the absorption of the products bythe active substance, which is removed after saturation with moleculesthat include metal atoms. Electrolysis of water in flotation reactors inthe presence of an active substance based on the aluminum, titanium,sodium, iron atoms and hydrogen peroxide, metal electrodes (stainlesssteel, copper, aluminum) or carbon material in a special reactor with adirect current voltage of 3 to 240 V and current density on electrodeswithin the range of 0.01 to 2 A/m², which generates an additional numberof OH-ions, O₂ molecules and other active substances accelerating theoxidation rate for organic molecules and reducing the residence time ofthe water in the flotation reactor, with subsequent separation of theactive substance from water in an electric filter of a specialconstruction. Water disinfection in one or more electrochemical reactorsof a special construction with ultraviolet radiation, ultrasonic waves,cavitation waves, which are formed in water by direct current pulses inthe range from 300 to 3000 V to three titanium electrodes (two positiveand one negative) in the reactor with metal or metals particles loadedin between the electrode space (iron, aluminum, copper separately or incombination in different ratios) in the size from 3 to 10 mm, whichgenerates from 0.1 to 30 mg/l of the active substance based on the iron,copper and aluminum, titanium oxides, with or without addition of NaClin a concentration of 0.5 to 30 g/l, with or without the addition ofhydrogen peroxide in the range of 0.5 to 10 ml/l. Oxidation of organicmatter residues in two or more high pressure reactors by their oxidationwith OH-, O- and O₂ molecules, which are formed from the decompositionof water and hydrogen peroxide molecules on the surface of an activesubstance absorbing organic molecules and generating OH- and O-ions onits surface, which react with nearby organic molecules, the reactionproceeds with the formation of free radicals of organic molecules whichare active and enter the recombination reaction between themselves anddeeper oxidation due to the reaction with the OH-, O-ions under highpressure, and the pressure in the reactor increases due to the releaseof the active oxygen (preferably), which is dissolved in water underhigh pressure, at pH of less than 4 and pressure in the range from 3 to10 atm, in the presence of hydrogen peroxide (20% of total requiredvolume) in relation to the active substance in the range from (1:0.5) to(1:5) when the active substance is separated from the water byfiltration of the sediment on the kieselguhr filter in the process ofwater overflow into the next reactor of elevated pressure. Oxidation ofthe organic matter remaining in water in two or more high pressurereactors in the range from 2 to 10 atm, on activated carbon with reactorfilling of 60-90% by volume in the presence of hydrogen peroxide (20%volume) under high pressure maintained by water pressure from a previoushigh pressure reactor and additionally generated by active oxygenreleased at pH over 6, the pH of the solution is regulated by addingcalcium oxide to meet the required pH level from previous level. Furtherwater filtration is performed on one or more precoat filters usingkieselguhr as a filter element to remove solid particles larger than 5microns. If necessary, further water purification from metal ions andnonmetals is carried out by dialysis in one or more reactors and, ifnecessary, further water filtration in one or more charcoal filters.Then the reactors are filled with water, the time of water in each ofthe reactors, the water level in the reactors, the rate of water supplyon the filters and in the electrochemical reactor, the foam removal isregulated and controlled by an automatic control system for the processwith given, for a certain water parameters, such as pH, the reactiontime, the amount of active substance, the hydrogen peroxide amount, theamount of calcium oxide, the rate of water supply, Total DissolvedSolids (TDS), Reduction-oxidation reaction (RedOx), etc.

The invention claimed is:
 1. A method for treatment and disinfection ofan aqueous industrial effluent comprising organic pollutants selectedfrom the group consisting of saturated fats, unsaturated fats, oil,petroleum products and organic solvents, the method comprising: formingan aqueous suspension by mixing the effluent with a hydrophobiccarbon-based sorbent in powder form capable of absorbing the organicpollutants; absorbing at least some of the organic pollutants on thecarbon-based sorbent to form a pollutant-laden carbon-based sorbent;separating solid particles, including the pollutant-laden carbon-basedsorbent, from water in the effluent by filtering the aqueous suspensionthrough a volume of rubber-based hydrophobic sorbent to, thereby,produce treated water that is substantially free of organic pollutants;absorbing at least some of the organic pollutants on the rubber-basedsorbent during the filtering step to form pollutant-laden rubber-basedsorbent; pyrolytically decomposing, free of oxygen, the pollutant-ladencarbon-based sorbent and the pollutant-laden rubber based sorbent tosynthesis gas comprising carbon monoxide and hydrogen; performing frothflotation in a continuous manner to generate a foam, including addinghydrogen peroxide to the treated water in presence of a metal catalystso as to allow absorbing of organic molecules and heavy metals in thetreated water by the foam; removing the foam and disposing thereof;removing the metal catalyst for reuse; performing electrocoagulation onthe treated water in a continuous manner using non-sacrificial carbon ormetal electrodes, and sacrificial electrodes based on the aluminum,titanium, sodium, tin, copper, and other metals having atoms that absorborganic compounds on its surface as foam is removed at atmosphericpressure; water disinfection by electrocavitation, which is formed byhigh-voltage discharges in the medium of iron and copper particles, oralloys based upon iron and copper particles, with disintegratingtitanium electrodes; performing further oxidation of organic matter inthe treated water using iron and titanium atoms for further organicmatter oxidation, decomposition of the organic matter a continuousmanner in the presence of hydrogen peroxide and iron, titanium, copper,sodium, or other metal atoms with calcium oxide (CaO) and activatedcarbon at high pressure; water filtration on a precoat filter underpressure to remove solid and colloidal particles of more than 5 micronsfrom water, wherein a substrate of the filter comprises kieselguhr andthe filter includes a precoat membrane having at least one of aluminum,titanium, copper, and sodium removing ions from the treated water by anelectrodialysis step; and filtering the treated water through anactivated carbon filter.
 2. The method of claim 1, wherein the saturatedand unsaturated fats, oil and petroleum products, organic solvents, areremoved from the effluent by adding the carbon and rubber sorbents,followed by the cleavage of the removed substance by pyrolysis using themicrowave radiation energy, which generates combustible synthesis gas,followed by the use of the synthesis gas to generate thermal andelectric energy.
 3. The method of claim 1, wherein the oxidation takesplace on the surface of the organic matter based on the aluminum,titanium, sodium, iron atoms which are a catalyst.
 4. The method ofclaim 1, wherein the electrocoagulation of the treated water occurs inflotation reactors and the non-sacrificial electrodes and sacrificialelectrodes are provided with a direct current voltage of 3 to 240 V anda current density within the range of 0.01 to 2 A/m2.
 5. The method ofclaim 1, wherein the disinfection of the treated water is carried out inan electrochemical reactor by ultraviolet radiation, ultrasonic waves,cavitation waves, which are formed in water by direct current pulseswithin the range from 300 to 3000 V on titanium electrodes.
 6. Themethod of claim 1, wherein the oxidation of the organic matter takesplace with activated carbon and hydrogen peroxide in a high pressurereactor, with a pressure from 2 up to 10 atm.
 7. The method of claim 5,further comprising, locating within an inter-electrode space, betweenthe titanium electrodes, metal particles in size from 3 mm to 10 mm. 8.The method of claim 7, further comprising, adding NaCl in aconcentration of 0.5 to 30 g/l, to the high pressure reactor.
 9. Themethod of claim 8, wherein the hydrogen peroxide in the high pressurereactor defines a concentration from 0.5 to 10 ml/liter.
 10. The methodas set forth in claim 7 wherein the metal particles are at least one ofiron, aluminum, copper, and combinations thereof.